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Product Description:

Men's NEWTON® RUNNING SIR ISAAC S :: Maintain more control of your run with the men's Newton® Running Sir Isaac S. Land smooth and stable through every step with tapered forefoot lugs and midfoot chassis. It's easy to transition from a heavy heel-strike running style to a more centered, natural position with Newton's unique beveled heel and toe design. Stay super cool with highly breathable mesh. 10.9 ounces

Category Type:

STABILITY[?]
Runners with average arch height looking for a blend of cushioning and support can't go wrong with Stability shoes. Get a smooth transition from heel strike to toe off.
Enjoy a well-guided stride and perfect arch support to keep you going for miles.
When choosing running shoes, find your perfect fit using this chart. Category types are based on factors like arch height, running habits and body frame.

After switching from Kayano 20 to 21, I thought I might as well try more shoes and bought these + a pair of Saucony Hurricane 16 + a pair of Mizuno Wave Inspire 11, all being of stability type.I ran only 3 times with the Newton Sir Issac S so far, but decided to write a review anyway. First thing is that the shape in the front is kind of unique. It feels strange at first, but then it feels really good because the front of the foot seems to be in a better position to push forward. They must have done some research with this.I read reviews saying that the shoe was not durable. I cannot say anything about this yet. The construction looks fine even though the show feel very light compared to other stability (however I did not bother to look at the actual weight in the description :-)I don't mind much about the price or keeping the shoe for more than 350 miles anyway. What counts is that it helps me getting better and protects from injuries.Just try them if you are curious, it doesn't hurt! Also it's a smaller brand specialized in running shoes, so give them a fair shot.

I'm a heavier runner and I tend to be a midfoot / forefoot striker. As a result, I've been battling a lot of injuries for the last 8 years. My Physical Therapist mentioned this shoe as I finished my last round of PT, and it has made a world of difference for me. This shoe compensates for my natural tendency to run "up on my toes", allowing me to do so without injuring myself. I'm back to running now and am enjoying myself more than ever. Totally a game changer for me. Slightly higher cost is more than offset by improved durability. Total winner.

I had high hopes for these shoes but was severely disappointed. The shoes are comfortable, no problem there. My real complaint is the shoes are worn out in 100 miles. For what these shoes cost, I was expecting more. I'm going back to Brooks, then have done me well over the years.

I am a 60 year old runner, former high school and college cross country and track distance athlete, who ran pretty consistently until the early 90's, then stopped for a while, and started running again about 3 years ago. I've pretty much trained in Asics shoes since the 1980's, and really liked the Keyano, until the 18 and 19 disappointed me. I'm 6 feet and about 200 lbs., and a pronator. After buying and disliking the Keyano 19's, I started looking for a substitute. I bought a pair of Adidas Sequence 5's, and liked them. Someone told me about the Newton's, and after reading good reviews about them I also bought a pair of Motions, which weren't too shabby, for track and softer surface wear. Then I read some really good reviews about the Sir Isaac S shoes, and decided to try a pair for training. The first thing I noticed was that they were heavier than I had anticipated (the Motions were pretty light, and I thought the Isaacs might also have a lightweight feel, for a trainer). The fabric was not very breathable. I went on my first run (about 4.5 miles, some road, but mostly grassy river levee, park and golf course surface), and noticed that I could feel the lugs through the shoes. This made the bottom of my forefoot uncomfortable, and eventually produced a hot spot (more on the right foot than the left). The shoe did not feel like it had a very good stability feature. My left arch starting hurting after about 2 miles. Then my right outside low ankle started hurting after about 4 miles. Two days later I tried the shoes again (after running in my Sequence the day before). The arch burning and hot spot were back, and I had that same right ankle pain almost immediately. Also, the forefoot strike that the shoe promotes seemed to put a lot of stress on the insides and fronts of my knees. In short, my experience was very unpleasant. I returned the shoes, and am now waiting for a pre-order of Sequence 6's to come in. I'm also trying to find another good stability trainer (I'm not a minimalist or zero drop fan). After many years of being low maintenance and very pleased with almost every shoe I purchased, more recently it has become difficult to find a good stability trainer. I still miss the old Keyano's, the ones they made before Asics decided to follow the motto, "If it ain't broke, break it!"

This shoe is amazing its the first running shoe that i really noticed the differance i always ran in gel kayano but from now on aim a newton fan i really love this shoe its fits nice with my orthotics and is a nice light feeling to run w/good stability !

I am a 15-20 mile a week runner. Slow but steady, I have been building my endurance over the past 5 years of training. This shoe is absolutely a game changer. For some, shoes in truth really don't make a difference. For me the newton and the training videos on you tube have not only completely changed my running technique but have nursed a knee twist I suffered last year and never really got over with regular shoes. It is a no brainier to give this shoe a try with the 90 day guarantee. I am running in them for 6 weeks and am amazed by my progress to date.

2nd pair after a long run with Mizuno Nirvanas (excellent shoe)--found the Newton Sir Isaac S to be an excellent running shoe if your wanting to change to a forefoot running style. I realize everyone is different, but with me I lost running problems, injuries associated with being a heel-striker. Also I had a real issue with the big metatarsal on my left foot and with the newton SIs it has not been a problem. I just ordered my 3rd pair.

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